MOPS

Abstract: A mop including an integral wringing device allowing for selective wet- and dry-wringing, comprises: a handle (1; 102) terminating at one end in a head (3; 105) from which extend a plurality of absorbent mop elements (4; 104); a shroud (5; 116) rotatably mounted on the handle (1; 102) and slidable relative thereto between a withdrawn position in which the mop elements (4; 104) are exposed for mopping and an advanced position in which the mop elements (4; 104) are retracted within the shroud (5; 116), whereby the action of sliding the shroud (5; 116) relative to the handle (1; 102) from said withdrawn position into said advanced position effects a wet-wringing of said mop elements (4; 104) as they are retracted within the shroud (5; 116); and at least one wringing element (10; 130) mounted on or within the shroud (5; 116) and including a or a respective mop element-engagable portion (14; 134), the or each wringing element (10; 130) being deformable and/or movable so as to be configurable in either of a first position in which retraction of the mop elements (4; 104) into the shroud (5; 116) upon sliding of the shroud (5; 116) from said withdrawn position to said advanced position is relatively unhindered, and a second position in which, with the shroud (5; 116) in its advanced position and the mop elements (4; 104) retracted therewithin, the or the respective mop element-engagable portion (14; 134) of the wringing element or elements (10; 130) engage and grip the mop elements (4; 104) within the shroud (5; 116) upon rotation of the shroud (5; 116) relative to the handle (1; 102), whereby the action of rotating the shroud (5; 116) relative to the handle (1; 102) when the mop elements (4; 104) are retracted within the shroud (5; 116) and the wringing element or elements (10; 130) are configured in their second position, constitutes a dry-wringing of said mop elements (4; 104).

Description: MOPS FIELD OF THE INVENTION This invention relates to mops, that is to say cleaning devices comprising a handle and a plurality of elongate absorbent elements mounted at one end thereof for the purpose of cleaning surfaces such as floors. More particularly, the invention relates to a mop which incorporates a wringing device which enables the user to extract a desired amount of absorbed liquid from the mop elements to render them suitably prepared for a particular mopping application. BACKGROUND OF THE INVENTION AND PRIOR ART The most conventional means by which excess water or other liquid is removed from the elongate absorbent strips of a mop following rinsing thereof for example, comprises a perforated cradle attached to the top of one side of a container holding the water, so that downward pressure, usually also with a screwing action, of the mop elements into the cradle squeezes excess water therefrom, which re-enters the container through the perforations in the cradle. This somewhat crude wringing device has been replaced in many recent proposals by a wringing device integral with the mop itself. One known form of integral mop wringing device comprises a fluted or longitudinally furrowed shroud which is mounted on the mop handle so as to be slidable relative thereto. Sliding of the shroud relative to the handle into an advanced position in which the mop elements are retracted into the shroud causes the water-laden elements to be compressed and thus excess water squeezed out therefrom. The fluted or furrowed configuration of the shroud assists this squeezing action as the mop elements are retracted therewithin. This form of wringing device is disclosed for example in US-A- 5060338, DE-A-3607121 and US-A-3364512. In a development of this fluted or furrowed shroud arrangement, US-A-2365437 and GB-A-1300709 propose a spirally fluted sleeve, so that as the water- laden mop elements are retracted within the shroud, they experience a degree of twisting. This serves to increase the wringing action of the device, so that more of the absorbed water in the strips is ejected. These known integral wringing devices have limited efficacy as regards the amount of compression which can be exerted on the strip elements to squeeze water out of them. Thus, a further known form of integral mop wringing device employs a twisting action to squeeze water from the strip elements in a similar manner to the wringing of water from a conventional cleaning cloth. To achieve this twisting action, a shroud is again employed which is slidable along the mop handle so as to retract the strip elements therewithin, but provided on the interior of the shroud wall are a plurality of inwardly directed, longitudinally extending ribs or teeth which, when the shroud is rotated relative to the mop handle with which the strip elements are fast mounted, grip the strip elements so as to impose resistance upon their rotation with the relative rotation of the shroud. This action causes twisting of the strip elements and a resulting wringing action which squeezes water therefrom in a significantly more efficient manner than the older known devices mentioned above. Examples of this form of integral mop wringing device are described and illustrated in FR-A-2622785 and US1709622, for example. The general trend in the development of integral mop wringing devices such as those discussed above has been towards optimization of the available wringing action so that the amount of water which can be squeezed out of the mop elements can be maximised. However, we have now found this to be a significant shortcoming of known self-wringable mop designs and this is especially the case where mopping operations demand refinement as regards the wetness or dryness of the strip elements for different stages in an overall mopping regime. More particularly, in the cleaning of floors for example it is often required for an initial mopping stage that the absorbent strip elements are relatively wet, i.e. there is a relatively large amount of water absorbed therein. Accordingly, after the mop head has been immersed in a container of water, which may typically also contain detergent, it is desirable to squeeze out only a limited quantity of the absorbed water from the strip elements, so as to leave the strips relatively wet for cleaning purposes. The degree of wringing necessary to achieve this action is termed in the art, and herein, a "wet-wring". On the other hand, when it comes to a subsequent mopping stage after the major part of the cleaning process is complete, it is frequently necessary to dry off the floor or other surface as much as possible and for this purpose the strip elements of the mop must generally be relatively dry. Accordingly, for such later stages of a mopping operation, it is desirable that more extreme wringing action is available from the device, such that as much as possible of the absorbed water is squeezed out of the strip elements to leave them relatively dry for the final wiping off stage. The type of wringing action for this purpose is termed in the art, and herein, a "dry- wring". In the context of a mop which includes an integral wringing device capable of a wet-wring and a dry-wring, the above known types of mop incorporating wringing devices are inherently unsuitable, as they generally only permit one or other of these wringing actions. Although in certain of the known devices some variability in the wringing pressure may be able to be generated by the user, this is difficult, if not impossible, to control accurately such that optimum mop wetness is achieved for a given mopping application. The construction of these known mop wringing devices also limits the maximum amount of wringing pressure which can be applied, such that in many of the known devices there is a practical limit on the amount of wringing pressure available, which can therefore render such a mop inherently unsuitable for a drying off mopping stage. It would be an advantage for optimum multi-stage mopping applications, therefore, if there were to be available a mop which incorporates a wringing device which permits at least two different wringing actions, namely at least a "wet-wring" and a "dry-wring", selectable by the user in accordance with a desired degree of wetness of the mop elements required of a particular stage in the mopping operation. It is to this primary object that the present invention is directed. SUMMARY OF THE INVENTION Accordingly, in a first aspect the invention provides a mop comprising: a handle terminating at one end in a head from which extend a plurality of absorbent mop elements; a shroud rotatably mounted on the handle and slidable relative thereto between a withdrawn position in which the mop elements are exposed for mopping and an advanced position in which the mop elements are retracted within the shroud, whereby the action of sliding the shroud relative to the handle from said withdrawn position into said advanced position effects a wet-wringing of said mop elements as they are retracted within the shroud; and at least one wringing element mounted on or within the shroud and including a or a respective mop element-engagable portion, the or each wringing element being deformable and/or movable so as to be configurable in either of a first position in which retraction of the mop elements into the shroud upon sliding of the shroud from said withdrawn position to said advanced position is relatively unhindered, and a second position in which, with the shroud in its advanced position and the mop elements retracted therewithin, the or the respective mop element-engagable portion(s) of the wringing element or elements engage and grip the mop elements within the shroud upon rotation of the shroud relative to the handle; whereby the action of rotating the shroud relative to the handle, when the mop elements are retracted within the shroud and the wringing element or elements are configured in their second position, constitutes a dry-wringing of said mop elements. In a second aspect, the invention provides a method of mopping utilising the mop as defined above, the method including immersing the absorbent mop elements into a container of liquid, removing them therefrom and then carrying out one or both of the following wringing steps: (a) sliding the shroud relative to the handle of the mop from the withdrawn position into the advanced position to effect a wet-wringing of the mop elements as they are retracted within the shroud; (b) with the shroud in its advanced position and the mop elements retracted therewithin, and the wringing element or elements configured into their mop element- engaging position, rotating the shroud relative to the handle to effect dry-wringing of the mop elements. In the above dry-wringing step (b) the configuring of the wringing element or elements into their mop element-engaging position may be effected as a discrete step prior to commencing rotation of the shroud relative to the handle, or alternatively may be accomplished by the rotational action itself of the shroud relative to the handle, depending upon the form and construction of the wringing element(s). In this respect, therefore, various embodiments of the invention may differ in the form and construction, and manner of actuation, of the wringing element(s). According to a first preferred embodiment of the invention there is provided a mop comprising: a handle terminating at one end in a head from which extend a plurality of absorbent mop elements; a shroud rotatably mounted on the handle and slidable relative thereto between a withdrawn position in which the mop elements are exposed for mopping and an advanced position in which the mop elements are retracted within the shroud; and at least one wringing element provided within and fast with the shroud and deformably configurable in either of a first configuration in which retraction of the mop elements into the shroud upon sliding of the shroud from said withdrawn position to said advanced position is relatively unhindered, and a second configuration in which, when the mop elements are retracted within the shroud, at least a portion of the or each wringing element is deformed inwardly of the shroud so as to grip the mop elements as the shroud is rotated relative to the handle; whereby the action of sliding the shroud relative to the handle from said withdrawn position into said advanced position constitutes a wet-wringing of the mop elements as they are retracted within the shroud and whereby the action of rotating the shroud relative to the handle when the mop elements are retracted within the shroud and the wringing element or elements are in their second, mop element-gripping configuration, constitutes a dry-wringing of said mop elements. In connection with the above defined mop according to the first embodiment of the invention, there is also provided a method of mopping utilising the same, the method including immersing the absorbent mop elements into a container of liquid, removing them therefrom and then carrying out one or both of the following wringing steps: (a) with the wringing element or elements in their first configuration, sliding the shroud relative to the handle from its withdrawn position into its advanced position to effect a wet-wringing of the mop elements as they are retracted within the shroud; (b) with the shroud in its advanced position and the mop elements retracted therewithin, configuring the wringing element or elements into their second, mop element-gripping configuration, and rotating the shroud relative to the handle to effect dry-wringing of the mop elements. According to a second preferred embodiment of the invention there is provided a mop comprising: a handle terminating at one end in a head from which extend a plurality of absorbent mop elements; a shroud rotatably mounted on the handle and slidable relative thereto between a withdrawn position in which the mop elements are exposed for mopping and an advanced position in which the mop elements are retracted within the shroud, whereby the action of sliding the shroud relative to the handle from said withdrawn position into said advanced position effects a wet-wringing of said mop elements as they are retracted within the shroud; and • * at least one wringing element, preferably a plurality of wringing elements disposed angularly around the shroud, mounted swivellably relative to the shroud, the or each wringing element including a respective tooth portion protruding into the interior of the shroud and having a configuration and disposition relative to the swivel axis of the wringing element such that, with the shroud in its advanced position and the mop elements retracted therewithin, rotation of the shroud relative to the mop handle in a wringing direction causes engagement of the mop elements with the tooth portion(s) of the wringing element,s) and thereby swivelling of the or each wringing element about its respective swivel axis, said swivelling motion being from a non-mop element-gripping position, in which retraction of the mop elements into the shroud upon sliding of the shroud relative to the handle from said withdrawn position to said advanced position is relatively unhindered, into a mop element-gripping position in which the tooth portion(s) of the wringing element(s) grip the mop elements and effect dry-wringing thereof upon said rotation of the shroud relative to the handle in said wringing direction. In connection with the above defined mop according to the second embodiment of the invention, there is also provided a method of mopping utilising the same, the method including immersing the absorbent mop elements into a container of liquid, removing them therefrom and then carrying out one or both of the following wringing steps: (a) with the wringing element or elements in their first, non-mop element-gripping position, sliding the shroud relative to the handle from its withdrawn position into its advanced position to effect a wet- wringing of the mop elements as they are retracted within the shroud; (b) with the shroud in its advanced position and the mop elements retracted within the shroud, rotating the shroud relative to the handle to cause engagement of the tooth portion(s) of the wringing element(s) with the mop elements and thereby swivelling of the or each wringing element about its respective swivel axis, said swivelling being from said non-mop element-gripping position into said mop element-gripping position in which the tooth portion(s) of the wringing element(s) grip the mop elements and effect dry-wringing thereof upon said rotation of the shroud relative to the handle in said wringing direction. SUBSTITUTESHEET(RULE20) In accordance with the present invention, therefore, the above defined construction of mop with integral wringing device permits of two independent wringing actions of the absorbent mop elements: firstly, a wet-wring action accomplished by the longitudinal sliding of the shroud over the water(or other liquid)- laden mop elements in order to eject only a proportion of the water which is absorbed in the mop elements; and secondly, an independent dry-wring action for maximum ejection of water from the water(or other liquid)-laden mop elements accomplished by twisting of the shroud relative to the mop handle with the wringing element or elements in their mop element-gripping configuration or position, which, as mentioned above, may be accomplished either in a discrete configuring step or alternatively as a result of the twisting action of the shroud itself. With the known constructions of mop with integral wringing devices, such independently selectable plural wringing actions are not possible. In the construction of mop according to this invention, the size of the shroud in the transverse direction relative to the longitudinal axis defined by the handle is preferably designed so that a predetermined amount of wet-wring pressure is applied to the water-laden mop elements as they are retracted into the shroud. The dimensions of the shroud may therefore be selected for optimum wet-wring action in accordance with the number, distribution and size (both under maximum absorbtive water retention and under a degree of water retention for optimum wet-mopping) of the mop elements of the mop in question. Since the degree of water excretion for optimum dry-wringing action is defined simply by a maximum and not by a selected value within a possible range, in the context of the first preferred embodiment of the invention defined above the maximum dry-wringing pressure available from the device will generally be defined by a practical limit on the amount of inward deformation of the wringing element or elements and the overall strength and rigidity of the components of the device. In the context of the second preferred embodiment defined above, the maximum dry-wringing pressure available from the device will generally be defined by a practical limit on the angle through which swivelling of the wringing elements can occur as they grip the mop elements with increasing force as the shroud is rotated relative to the handle in the defined wringing direction. It may also be limited to some extent by the overall strength and rigidity components of the device. In a preferred construction of mop according to the first preferred embodiment, the shroud, which is appropriately dimensioned and is that part which enshrouds the mop elements when it is in its advanced position, is integrally joined at its end remote from its open end to a sleeve which is preferably of smaller transverse dimension than the shroud and which slidably accommodates the mop handle, along which the sleeve can be slidably displaced by the user. Preferably the sleeve and the mop handle include respective elements of at least one retention clip arrangement, for locking the shroud relative to the handle in at least one of its relative withdrawn and advanced positions. Most desirably, there is provided such a clip arrangement which allows the shroud to be locked in its relative withdrawn position, since it is in this condition that mopping will be carried out and thus require the shroud to be anchored against unintentional sliding down the mop handle under gravity. A corresponding clip arrangement provided further down the mop handle towards its head, for locking the shroud in its relative advanced position, is optional. In preferred mop constructions according to this first embodiment, there are provided a plurality of, preferably at least two, more preferably three or four, or even up to about six, wringing elements disposed equiangularly within the shroud. It is especially preferred that, however many wringing elements there are (most preferably at least two e.g. three), they are disposed equiangularly within the shroud, and thus equidistant from each other, in order to generate angularly balanced radially inward forces during the dry-wringing action. This optimises the distribution of dry-wringing forces and helps to reduce unbalanced stress concentrations in the structure which could lead to weakening of mechanical parts or component failure. Whilst the shroud may be cylindrical or possibly even elliptical in cross-section, it may alternatively advantageously be formed with a generally triangular or square cross-section, for example where there are, respectively, three or four wringing elements provided in the apparatus. In the case of a polygonal cross- sectioned shroud, each of the wringing elements is preferably disposed mid-way along one side of the polygon, opposite a respective vertex thereof. In particularly preferred mop constructions according to this first embodiment, each of the wringing elements which is disposed within and preferably adjacent the inner wall of the shroud is elongate and comprises a foot which is anchored to the shroud at or near its lower, open end, and the other, upper end of the wringing element is attached to a common collar which surrounds and is slidable relative to the sleeve attached to the shroud. Intermediate the two ends of each wringing element, preferably towards its foot end, is provided a radially inwardly deformable knee segment which deforms radially inwardly of the shroud when tensile compression is applied to the wringing element as force is applied which urges a reduction in the distance between its foot and head ends. This co pressive action results from a sliding of the collar relative to the sleeve, so that there is an effective reduction in the distance of the collar from the anchored foot of the wringing element. Optionally, there may be provided a locking clip for locking the collar relative to the sleeve with the wringing element or elements in their radially inwardly deformed, mop element-gripping configuration. In this condition, therefore, rotation of the mop handle (and thus mop head) relative to the shroud can be effected easily by manual manipulation by the user. The relative rotation can be in either rotational direction, i.e. clockwise or anticlockwise, depending for example on the preference or mannual ease of the user. Upon such relative rotational movement, by virtue of the resistence to rotation imposed on the mop elements by the wringing elements, the mop elements experience an overall twisting which thereby compresses them to eject absorbed water therefrom in accordance with the desired dry-wring action. The amount of dry-wring pressure applied to the mop elements may be increased by further twisting of the shroud relative to the handle. However, as will be appreciated, depending upon the strength and rigidity of the overall construction, an upper limit on the practical dry-wringing force will generally be experienced, but as with conventional mops will readily be able not to be exceeded by practical experience. In the above defined most preferred construction, therefore, the wet-wring action of the wringing device is achieved by a manual grasping of the sleeve and a sliding of it relative to the mop handle towards the mop head so that the water(or other liquid)-laden mop elements are retracted therewithin and, under that action, experience a partial compression to partially excrete water absorbed therein. Once in this position, if wanted the dry-wring action of the device is accomplished by the manual grasping of the collar to which are attached the upper ends of the wringing elements and a forcing of this collar towards the lower, open end of the shroud so as to deform radially inwardly the knee segments of the wringing elements, which thereby grip the mop elements within the shroud. Then, by rotating the shroud or handle relative to the other of those components, a twisting of the mop elements within the shroud is effected so as to excrete a maximum amount of water therefrom, thereby accomplishing a dry- wring action. To expose the now "dry" mop element for further mopping action, any relative rotational force between the shroud and the handle is relaxed, the collar of the wringing element deforming arrangement is withdrawn in an upward longitudinal direction to remove the inward deformation of and thus straighten the knee segments of the wringing elements, and the shroud is then retracted in an upward longitudinal direction so as to expose the mopping elements, in which condition they are ready for further mopping. Preferably, both of those upward sliding movements of collar and shroud will be effectable sequentially in what is essentially a single, combined follow-through sliding action. In a preferred construction of mop according to the second preferred embodiment defined above, the shroud includes a cage in which are swivellably mounted the wringing elements, the cage preferably being integral with the shroud and thus fast therewith, so that rotation of the cage relative to the handle is achieved by a corresponding relative rotation of the shroud. Preferably the shroud, which is appropriately dimensioned and is that part which enshrouds the mop elements when it is in its advanced position, is integrally joined at its end remote from its open end to a sleeve which is preferably of a narrower transverse dimension than the shroud and which slidably accommodates the mop handle, along which the sleeve can be slidably displaced by the user. Preferably the sleeve and the mop handle include respective elements of at least one retention clip arrangement, for looking the shroud relative to the handle in at least one of its relative withdrawn and advanced positions. Most desirably, there is provided such a clip arrangement which allows the shroud to be locked in its relative withdrawn position, since it is in this condition that mopping will be carried out and thus require the shroud to be locked in its relative withdrawn position and thus require the shroud to be anchored against unintentional sliding down the mop handle under gravity. A corresponding clip arrangement provided further down the mop handle towards its head, for locking the shroud in its relative advanced position, is optional. In more preferred mop constructions according to this second embodiment, the cage, which may be open or (more preferably) closed to the exterior of the apparatus, surrounds one or more openings in the shroud wall through which protrude the tooth portions of the wringing elements for gripping of the mop elements during the dry-wringing operation of the apparatus. The opening or openings in the shroud wall may be constituted by a single continuous opening or, more preferably, by discrete apertures defined by the edges of partitioning sections of the shroud wall, which sections are contiguous with the walls of the shroud immediately above and below the cage. The cage preferably surrounds just a section of the shroud, preferably a section of the shroud near or towards its lower, open end, so as to leave the rest of the shroud operative for the wet-wringing action upon the mop elements when retracted therewithin. In preferred constructions of mop according to the second embodiment, the shroud includes a plurality of smooth-faced, longitudinally extending, generally radially inwardly projecting ribs on its inner wall. These ribs preferably extend along a major proportion of the shroud's height, particularly along that section of the shroud which contacts the mop elements when they are retracted therein for effecting the wet-wringing operation. The ribs are preferably discontinuous in the section of the shroud which defines the cage wherein are mounted the wringing elements of the wringing device. The function of these ribs is not for effecting any wring-inducing twisting of the mop elements as the cage is rotated relative to the mop elements, but instead to assist in advantageous shaping of the collection of mop elements so as to make their pushing-out easier when the shroud is withdrawn, both after a wet-wringing operation and after a dry-wringing operation. These functions of the ribs are explained in more detail further hereinbelow, in connection with the specifically described preferred embodiments of the mop of the invention. The cage of the wringing apparatus is preferably defined by a pair of continuous annular flanges or a plurality of discrete flanges extending outwardly from the periphery of the above defined opening or openings in the shroud wall, the flanges providing anchoring points for the means, e.g. axles or swivel pins, defining the swivel axes of the wringing elements. Preferably the swivel axes of the wringing elements are substantially parallel to the longitudinal axis of the mop defined by the handle, with the tooth portions of the wringing elements protruding generally inwardly of the cage into the interior of the shroud through the one or more respective openings in the shroud wall. In preferred mop constructions according to this second embodiment, there are provided a plurality of, preferably at least two, more preferably three or four, or even up to about six, wringing elements disposed equiangularly around the shroud. It is especially preferred that, however many wringing elements there are (most preferably at least two), they are disposed equiangularly around the shroud, and thus with their respective swivel axes equidistant from each other, in order to generate angularly balanced radially inward forces during the dry-wringing action. This optimises the distribution of dry-wringing forces and helps to reduce unbalanced stress concentrations in the structure which could lead to weakening of mechanical parts or component failure. In most preferred constructions of mop according to the second embodiment, the shroud has a generally cylindrical shape, especially a generally substantially circular cross-section in at least that section of the shroud in which the cage is provided with the wringing elements mounted therein. In an especially preferred construction of mop in accordance with the second embodiment of the invention, three wringing elements are provided, though four may also be suitable. Each of the wringing elements is preferably arranged with its swivel axis disposed towards the exterior of the cage, with its tooth portion protruding generally radially inwardly from a longitudinal edge of the wringing element opposite its swivel axis. The tooth portions of the wringing elements may be shaped in any suitable configuration, but preferably they are shaped so as to maximise the degree of gripping force which they exert on the mop elements within the shroud as the cage rotates relative to the mop handle. In addition to the features already mentioned, a preferred wringing element has extending from the said longitudinal edge a first side face contoured such that at least a portion of it abuts, as the wringing element swivels from its non-mop element- gripping position to its mop element-gripping position, an edge of a partitioning wall section of the shroud defining one side of the opening through which protrudes the tooth portion of that wringing element, and extending also from said longitudinal edge but in a different direction from the first side face, a second side face contoured such that at least a portion of it abuts, as the wringing element swivels from its non-mop element-gripping position to its mop element-gripping position, an edge of a wall section of the shroud defining the opposite side of the .opening through which protrudes the tooth portion of that wringing element. This abutment of both running side faces of the wringing elements helps to partition and prevent entanglement of the mop strip elements and to compress them for wet wringing. It also helps to direct the excreted water to the open end of the shroud. Projecting from the said first side face distal from the said longitudinal edge is preferably a first end stop which defines a swivel limit on the swivelling movement of the wringing element into the said mop element-gripping position, and projecting from the said second side face, also distal from said longitudinal edge, is preferably a second end stop which defines a swivel limit on the swivelling movement of the wringing element into the said non-mop element-gripping position. In this preferred form of wringing element, the second side face has a longer length than the first side face and preferably at least part of the second side face is contoured to match the peripheral contour of the adjacent partitioning wall sections defining the opening(s) in the shroud when the wringing elements are in their non-mop element-gripping positions, which peripheral contour of the said opening(s) is preferably, though not necessarily, generally substantially circular. In this preferred form of wringing element, at least a portion of each side face adjacent said longitudinal edge, preferably the portion thereof towards the upper end of the wringing element and above the portion which is contoured to abut the edge of a respective partitioning wall section of the shroud so as to present an upwardly and radially outwardly sloping ramp face, the purpose of which is to assist the pushing out step of the dry-wring operation when the shroud is to be withdrawn to expose the dry-wringing mop elements ready for use. This function is described in detail further hereinbelow, in connection with the specifically described preferred forms of mop in accordance with the second embodiment of the invention. Upon relative rotational movement of the cage relative to the handle of the mop in the defined wringing direction (which may be indicated to the user by visible indicia, e.g. arrows, provides on the mop), by virtue of the resistance to rotation imposed on the mop elements by the wringing elements, which grip the mop elements with increasing force as rotation of the cage relative to the handle advances, the mop elements experience an overall twisting which thereby compresses them to eject absorbed water therefrom in accordance with the desired dry-wring action. The amount of dry- wring pressure applied to the mop elements may be increased by further twisting of the cage relative to the handle. However, as will be appreciated, depending upon the strength and rigidity of the overall construction, an upper limit on the practical dry- wringing force will generally be experienced, but as with conventional mops will readily be able not to be exceeded by practical experience. In the above defined most preferred construction, therefore, the wet-wring action of the wringing device is achieved by a manual grasping of the sleeve and a sliding of it relative to the mop handle towards the mop head so that the water(or other liquid)-laden mop elements are retracted therewithin, and, under that action, experience a partial compression to partially excrete water absorbed therein. Once in this position, the dry-wring action of the device is accomplished by manually grasping the sleeve and effecting a rotation of the shroud or handle relative to the other of those components in the wringing direction, to effect the defined swivelling and the defined increasingly strong mop element-gripping action of the wringing elements, so as to excrete a maximum amount of water from the mop elements, thereby accomplishing a dry-wring action. To expose the now "dry" mop elements for mopping, any relative rotational force between the shroud and the handle may be relaxed and the shroud can then be simply withdrawn in an upward longitudinal direction so as to expose the mopping elements, in which condition they are ready for mopping. Due to the preferred construction and shape of the wringing elements, this upward withdrawal of the shroud is not hindered by the tooth portions of the wringing elements, because they automatically tend to swivel in the reverse direction back to their non-mop element-gripping positions under the force exerted against their respective upper ramp faces by the wrung, compacted collection of mop elements as the shroud is withdrawn. Thus, the preferred wringing elements make it possible for there to be a single, one stage push-out step once the dry-wringing operation is complete, without having to effect any untwisting of the mop elements which might otherwise be expected to be necessary given the nature of the dry-wringing mechanism. Of course, it is still possible, if necessary or if desired, possibly with alternative, less preferred constructions and/or shapes of wringing elements, to employ a degree of untwisting of the mop elements by reverse rotation of the shroud relative to the mop handle during the push-out stage of the dry-wringing operation. This push-out operation can also be effected at any stage of the wet-wringing action of the device, i.e. push-out can be effected even after only partial wet-wringing has been carried out. Thus, it is not essential for complete wet-wringing to have been effected before the push-out operation can be carried out. However, it is preferable that such complete or substantially complete wet-wringing is completed before the push-out stage, in preferred methods of this second embodiment of the invention. The simplicity of the above defined preferred constructions of mop in accordance with the first and second preferred embodiments of the invention permits substantially the whole apparatus to be made of moulded plastics material, which contributes to the ease and economy of manufacture of the mop and integral wringing mechanism. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION Preferred embodiments of mops according to the present invention, and in particular preferred aspects and features thereof, will now be described in detail, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a preferred mop with integral wringing device, according to a first embodiment of the invention: Figure 2 is a cross-sectional view of the mop shown in Figure 1, corresponding to the view on arrows II-II in Figure 3, showing a preferred construction of shroud and associated wringing elements; Figure 3 is a longitudinal sectional view on arrows III-III of Figure 2 of the lower section of the mop showing the component parts in their wet-wring operative configuration; Figure 4 is a longitudinal sectional view, corresponding to that of Figure 3, of the lower section of the mop showing the component parts in their dry- wring operative configuration; Figure 5 is an enlarged cross-sectional view of the lower section of an alternative preferred construction of the shroud and wringing elements, still in accordance with the first embodiment, with the mop strip elements omitted, showing a wringing element in its dry-wring configuration; Figure 6 is a cross-sectional view of the alternative embodiment on line VI-VI in Figure 5, Figure 7 is a perspective view a preferred mop with integral wringing device, according to a second embodiment of the invention; Figure 8 is a longitudinal median cross-sectional view of the mop shown in Figure 7; Figure 9 is a part-sectional view on arrows IX-IX in Figure 8 (viewed from the open end of the shroud looking up inside), showing the preferred construction of wringing device with the wringing elements in their wet- wring configuration; Figure 10 is a part-sectional view on arrows X-X in Figure 8, corresponding to the view shown in Figure 9, but in which the wringing elements are in their dry- wring configuration; Figure 11 is a part-sectional view on arrows XI-XI in Figure 8 (viewed from inside the shroud looking down and out of the open end), i.e. corresponding to the view shown in Figure 10, but from the opposite end of the shroud, showing the wringing elements in their dry-wring push-out configuration; Figure 12 is a part-sectional view on arrows XII-XII in Figure 8, corresponding to the view shown in Figure 11, showing the wringing device with the wringing elements in their intermediate wet-wring push-out configuration; and Figures 13(a), (b) and (c) are, respectively, top plan, front elevational and left side elevational views of the preferred wringing element of the apparatus of Figure 7. Referring firstly to Figures 1 and 3, the exemplary mop according to the first embodiment of the invention comprises an elongate handle 1, optionally fitted with end grip 2, and fast mounted on its lower, remote end a mop head 3 carrying and having extended therefrom a plurality of elongate absorbent strip elements 4. The strip elements may be attached to the head 3 by known means and may be of any suitable material and construction. They may, for example, comprise a homogeneous blend of viscose fibres and thermoplastic (e.g. polypropylene) fibres. Any other suitable material for the mop strip elements, however, may be used, as is well known in the art. In use, the strip elements 4 are immersed in a container, e.g. a bucket, of water or detergent composition, for the purpose of wetting ready for mopping or for rinsing, as the case may be, and as is standard in the mopping art. If desired, there may be provided on the handle a secondary grip portion a short distance above the upper limit of travel of the shroud, to assist mannual operation of the wringing device. Mounted on the lower section of the mop handle 1 is shroud 5 which is integrally attached to sleeve 6 which is in sliding engagement with the mop handle 1. In most instances, the mop handle 1 will be cylindrical and so the sleeve 6 will also generally be cylindrical. In the illustrated embodiment the shroud 5 has a curved triangular cross-section, as seen in Figure 2. The junction between the sleeve 6 and the shroud 5 preferably incorporates a shoulder 11 which abuts a corresponding outwardly extending flange portion formed on the mop head 3, so as to constitute a lower stop to limit downward sliding motion of the shroud relative to the handle 1. In the illustrated embodiment, the upper end of the sleeve 6 presents a radially inwardly directed protrusion 7 for interengagement with a corresponding recess 8 formed in the mop handle 1, interengagement of these two features acting as a clip to lock the shroud 5 and handle 1 in their relative advanced position as illustrated in Figure 3. Similarly, and more preferably, a corresponding clip arrangement is provided further up the mop handle towards the end grip 2, by provision of a corresponding recess (not shown) with which the same protrusion 7 can engage, for locking the shroud in its withdrawn position relative to the handle, in which position the strip elements are securely exposed for mopping, as shown in Figure 1. As an alternative to the above described retention clip construction, the same function may be achieved by frictionally intermating skirts, one fixedly mounted on the handle at the appropriate longitudinal position and the other formed on the sleeve. When the shroud 5 is moved from its retracted position as shown in Figure 1, in which the mop strip elements 4 are wholly or substantially wholly exposed for mopping, into its advanced position as shown in Figure 3 by relative sliding of the shroud relative to the handle, the strip elements 4 are retracted into the shroud 5 and compressed together therewithin. If, therefore, the strip elements 4 are previously water- laden, then such compression causes partial excretion of water therefrom, thereby leaving the strip elements 4 suitably wet for use in a wet-mopping application. From the position shown in Figure 3, therefore, the mop elements 4 are exposed for mopping by releasing the optional clip arrangement 7,8, sliding the shroud 5 upwardly relative to the handle 1 to allow the strip elements 4 to emerge from the lower, open end of the shroud 5, and securing the preferred second retention clip arrangement to lock the shroud in that withdrawn position. Referring to Figures 2 and 3, disposed in an equispaced fashion around the interior of the shroud 5 are three (or however many are appropriate to the shape of the shroud 5) elongate wringing elements 10. Each wringing element 10 takes the form of a substantially rigid elongate strip which terminates at its lower end in a foot 13 which is anchored at or near the lower, open end of the shroud 5 by means of its extending through a respective aperture in the shroud wall adjacent that open end and being locked therein by means of a hooked toe 12. The opposite, upper end of each wringing element 10 is attached, preferably integrally, to a common collar 9 which surrounds and is longitudinally slidable about the sleeve 6. The collar 9 provides the means by which the user can actuate the wringing elements to grip the mop strips 4, and so is necessarily on the outside of the apparatus, and may of course be provided with grip means on its outer surfaces, as also can the outer surface of sleeve 6. Each of the wringing elements 10 therefore passes through an aperture in or adjacent to the shoulder portion 11 which separates the shroud 5 from the sleeve 6. In an alternative construction, the collar 9 may take the place of the sleeve 6 and thus itself provide the sliding attachment to the handle 1, with the upper end of the shroud 5 terminating in a skirt which extends a short distance upwards from the upper limit of the shroud proper to lie outside the lower end of the collar to which are attached the tops of the elongate wringing elements 10. Towards the lower end of each wringing element 10 (which is the most preferable location for the means for gripping the mop strip elements 4 for causing twisting thereof) is formed an inwardly deformable knee section 14 defined by three hinge points 15. Each of these hinge points 15 may be defined by a line of reduced thickness of the material from which the major part of the wringing element 10 is formed. Any other suitable hinging means may alternatively, be employed, however. Given that the foot 13 of each wringing element 10 is anchored with respect to the shroud 5, tensile compressive force exerted on each wringing element 10 by manually forcing sliding movement of the collar 9 towards the open end of the shroud 5 causes an inwardly directed deformation of the knee section 14 of the wringing element 10 as a result of hinging motion at the three hinge points 15, as shown in Figure 4. As shown in Figure 4, each of the segments 14 of the knee section of the wringing elements 10 between the hinge points 15 is relatively stiff like the rest of the wringing element 10, so as to create an inwardly pointing knee which presses against and will act to grip the mop strip elements 4 as they are urged to twist relative to the shroud 5 upon relative rotation of the mop handle 1 relative to the shroud 5 by the user. Under this action, the strip elements 4 become twisted and thereby compressed, thereby resulting in a substantial wringing action which causes maximum excretion of absorbed water therefrom, so that this action constitutes a dry-wring mode of operation of the device. The amount of inward deformation of the knee 14 of each wringing element 10, which generally determines the degree of gripping action of the knee sections 14 and thus the overall magnitude of dry-wring pressure exertable by the device, can be varied within certain limits by the permitted amount of sliding motion of the collar 9 relative to the sleeve 6. To prevent rupture or excess bending of the hinge points 15 of the wringing element 10, a downward stop limit for movement of the collar 9 can readily be defined by the lower periphery of the collar 9 abutting the upper surface of the shoulder 11 of the shroud. An upper stop limit on the sliding motion of the collar 9 is, of course, defined by the maximum length of the wringing elements 10 as shown in Figure 3, when retraction of the strip elements 4 into the shroud upon wet-wringing is relatively unhindered by the wringing elements 10, which in this condition are disposed adjacent the inner wall of the shroud 5. From the relative positioning of the component parts of the apparatus shown in Figure 4, once dry- wringing is complete and it is desired to once again expose the strip elements 4 for dry-mopping, the wringing elements 10 can be released from their mop element-gripping configuration by upward sliding of the collar 9 relative to the sleeve 6, so as to once more assume the wet-wring configuration shown in Figure 3. From this position, further upward sliding of the sleeve 6 relative to the handle 1 withdraws the shroud 5 from around the mop strip elements 4, thereby exposing them ready for use. Referring now to Figures 5 and 6, here there is shown an alternative, more preferred construction of wringing elements and lower section of the shroud, still in accordance with the first embodiment of the invention. The mop strip elements are omitted from the Figure for clarity. In this alternative embodiment, the knee segment of each wringing element 10' comprises at least one flange extending generally radially outwardly of the shroud and away from the inner face of the knee segment which contacts and grips the mop strip elements. As shown, the upper, 14a, and lower, 14b, knee segments each have extending from their sides a pair of side flanges 16a, 16b, the former of which are seen more clearly in Figure 6. The side flanges 16b on the lower knee segment 14b are more narrowly spaced than the side flanges 16a on the upper knee segment 14a (or vice versa), so that as the upper and lower knee segments 14a, 14b pivot about the hinge point 15', the flanges overlap one another. In a further alternative, thought less preferred construction, each knee segment 14a, 14b has only one flange projecting from it, preferably from its centre. Where two side flanges are provided on each knee segment, they may if desired be joined by a rear wall. The importance of the above described flange(s) extending outwardly from the mop strip element-gripping knee segments is for preventing the mop strip elements from getting tangled up around, especially behind, the wringing elements as the strips are twisted during the dry-wringing action. To optimise this function, the radially outward end of each flange preferably extends sufficiently outwardly so as to leave substantially no gap or only a small gap at most between it and the adjacent inner walls of the shroud. In order to accomodate the flange(s) when the wringing elements are brought into their non-mop element-gripping configuration, the shroud is preferably provided with appropriately sized and shaped apertures 19 (Figure 6) into or through which the flanges protrude when the wringing elements assume this position. Alternatively, the shroud moulding itself may be provided with appropriately sized and shaped recesses to fulfil the same function, which has the additional benefit of shielding the moving parts of the wringing apparatus from the outside. The mop handle 1 may be made of any suitable material, such as wood or plastics, as is well known in the art. The component parts of the wringing device of the apparatus, namely the shroud, sleeve and the wringing elements can all conveniently be moulded from plastics material, thereby making the mop easy and cheap to manufacture. The following description relates to Figures 7 onwards, which show an exemplary preferred mop with integral wringing device according to the second embodiment of the invention. Referring firstly to Figures 7 and 8, the mop of this embodiment comprises an elongate handle 102, optionally fitted with end grip 103, and fast mounted on its lower, remote end a mop head 105 carrying and having extending therefrom a plurality of elongate absorbent strip elements 104. The strip elements 104 may be attached to the head 105 by known means and may be of any suitable material and construction. They may, for example, comprise a homogeneous blend of viscose fibres and thermoplastic (e.g. polypropylene) fibres. Any other suitable material for the mop strip elements, however, may be used, as is well known in the art. In use, the strip elements 104 are immersed in a container, e.g. a bucket, of water or detergent composition, for the purpose of wetting ready for mopping or for rinsing, as the case may be, and as is standard in the mopping art. Mounted on the lower section of the mop handle 102 is a shroud 116 which is integrally attached to sleeve 118 which is in sliding engagement with the mop handle 102. In most instances, the handle 102 will be cylindrical and so the sleeve 118 will also generally be cylindrical. The junction between the sleeve 118 and the shroud 116 preferably incorporates an internal shoulder or stop 119 which abuts a corresponding element formed on the mop head 105, so as to constitute a lower stop to limit downward sliding motion of the shroud 116 relative to the handle 102. Mounted on the handle 102 at a position near or at the upper limit of travel of the sleeve 118 is a grip element 108, which assists manipulation of the moveable parts of the apparatus for effecting the various wringing actions. This grip element 108 includes at its lower end one of a pair of interengageable retention clip elements, the other being provided on the upper end of sleeve 118, for locking the shroud 116 in its withdrawn position, as shown in Figure 7. Suitably, this retention clip arrangement is formed by frictionally intermating skirts, one on each of the grip element 108 and the upper end of the sleeve 118, though an alternative construction comprises one or more protrusions on one of those elements which are interengageable with one or more corresponding recesses on the other of those elements. If desired, a similar retention clip arrangement may be provided further down the mop handle 102, to provide a means for locking the shroud in its advanced position shown in Figure 8. When the shroud 116 is moved from its withdrawn position shown in Figure 7, in which the mop strip elements 104 are wholly or substantially wholly exposed for mopping, into its advanced position shown in Figure 8 by relative sliding of the shroud relative to the handle, the strip elements 104 are retracted into the shroud 116 and compressed together therewithin. If, therefore, the strip elements 104 are previously water- laden, then such compression causes partial excretion of water therefrom, leaving the strip elements 104 suitably wet for use in a wet-mopping application. From the position shown in Figure 8, the mop elements 104 are exposed for mopping by releasing any optional clip arrangement provided to lock the shroud in its advanced position and sliding the shroud 116 upwardly relative to the handle 102 to allow the strip elements 104 to emerge from the lower, open end of the shroud 116, and securing the preferred second retention clip arrangement to lock the shroud 116 in that withdrawn position. As shown in Figure 9, which shows the construction and arrangement of the wringing device in its wet-wring configurations, the inner wall of the shroud has a plurality of ribs 150 protruding inwardly from it into the interior of the shroud. These ribs 150 extend longitudinally from near the open end of the shroud along the major part of its height. Each rib 150 has a gently curved profile, as seen in Figure 9, and does not protrude so far inwards as to interfere with the dry-wringing action of the device, which is accomplished by the swivellable wringing elements 130 with their inwardly protruding teeth 134, as will be described later. The ribs 150 are equispaced around the inner wall of the shroud and are angularly positioned, as shown in Figure 9, such that they angularly coincide with or are in the proximity of the teeth 134 of the wringing elements 130 during their swivelling motion. In the position shown in Figure 9, the shroud 116 is fully advanced over the mop strip elements 104 which are wholly retracted therewithin, the wet-wring operation having been completed. The ribs 150 offer equispaced reduced radius pockets within the shroud, which serve to divide the bunch of strip elements 104 into segments. This makes their pushing-out of the shroud easier, as the strips are encouraged by their segmental division to travel solely longitudinally in the channels formed between the ribs, without jamming, as the shroud is withdrawn over them. The close proximity of certain of the ribs 150 to the teeth 134 of the wringing elements 130, which are in Figure 9 in their fully reverse swivelled position, eases the sliding of the strip elements 104 over the tips of the teeth 134 during that withdrawal of the shroud. The detailed description which now follows concentrates on the dry-wringing mechanism and function of the apparatus of the preferred mop according to the second embodiment of the invention. Referring now to Figures 8 to 13, formed towards the lower, open end of the shroud 116 is a cage 120 in which are mounted the moving parts of the apparatus which constitute the dry-wringing mechanism. The cage 120 is defined by a pair of spaced apart annular flanges 123, 124, which are preferably formed as an integral moulding with the walls of the shroud 116. The cage 120 includes three apertures providing access to the Interior of the shroud 116, each of these apertures being defined by longitudinally upright edges of three partitioning walls 140 which are disposed equiangularly around the cage's inner periphery. The configuration and positioning of these partitioning walls 140 are best illustrated in Figure 9 for example. The partitioning walls 140 define the general profile of the inner periphery of the shroud 116 in the region of the cage 120 and at least one of the side faces 138, 139, preferably the longer one 139 (see Figure 13) of each wringing element 130 is contoured to match the inner profile of the shroud when the wringing elements 130 are in their non-mop element-gripping swivelling position, as shown in Figure 9. Each of the three wringing elements 130 is mounted between the flanges 123, 124 by means of swivel pins 136, each of which defines a respective swivel axis substantially perpendicular to the plane of the flanges 123, 124 and thus generally parallel to the longitudinal axis of the shroud and the mop generally. Each of the wringing elements 130 is swivellable about its respective swivel axis between two limiting positions which are illustrated in Figures 9 and 10, respectively. The shape of each wringing element 130 is preferably designed so that during the swivelling motion between these two positions there is constant abutment between its side faces 138, 139 with the respective edges of the partitioning walls 140 which define the aperture through which protrudes the respective tooth 134 of that wringing element. The tooth 134 of each wringing element 130 is preferably moulded or otherwise manufactured integrally with the main body of the wringing element. Alternatively, the tooth 134 may be formed by an insert which may if desired be of a different material from the main body, for example when the tooth is desired to be particularly stiff or more resilient compared with the material from which the main body of the wringing element is made. (The mop element gripping portions of the teeth 134 are in any event preferably shaped so as to minimise physical damage to the mop elements, e.g. by not presenting sharp edges or burrs. ) Desirably, all the wringing elements may be swivel biassed so that their teeth 134 are biassed towards the interior of the shroud over a certain distance at the start of their swivelling travel from the position shown in Figure 9 towards that shown in Figure 10. The biassing may be for example by any suitable spring means, e.g. true spring members forming part of the mechanics of the apparatus or alternatively resilient parts of the apparatus mouldings. This inward biassing is advantageous for ensuring that all the wringing elements catch and grip the mop elements at the same time and to an equal extent as dry-wringing is effected, a feature which may be difficult to achieve as the heavy, water-laden mop elements fall under gravity towards the lower side of the shroud when the mop is held in a tilted position prior to the dry-wringing operation and thus tend to cause the wringing elements on the lower side of the mop to be urged outwards and the wringing elements on the upper side of the mop to fall inwardly. The tooth 134 of each wringing element 130, has a curved profile as illustrated in Figure 13(c), and extends inwardly of the cage from a longitudinally oriented edge of the wringing element 130 opposite its swivel axis 136 and defined by the junction of the contained side faces 138, 139, which extend from in opposite directions from each side of this longitudinal edge. Each of these side faces 138, 139 terminates at a point distal from the tooth 134 in a respective longitudinally oriented stop element 132a, 132b, for example in the form of a protruding flange or detent. As the wringing element 130 swivels about its swivel axis, these detents 132a, 132b define stop limits on the angle of swivelling movement. Figure 9 illustrates one limiting swivelling position of the wringing elements 130 in which detents 132b abut corresponding edges of respective partitioning walls 140, whilst Figure 10 illustrates the other limiting swivelling position in which detents 132a abut corresponding edges of adjacent respective partitioning walls 140. As the wringing elements 130 swivel between these defined stop limits, their teeth 134 move between the respective positions shown in Figures 9 and 10. In the position shown in Figure 9, which corresponds to a non- mop element-gripping position, only the tips of the teeth 134 protrude into the interior space within the shroud, in order that the teeth do not get dislocated beyond the illustrated non-mop element-gripping position. In this position the teeth 134 offer substantially no hindrance to retraction of the mop elements 104 into the shroud as the latter is slid relative to the handle from its withdrawn to its advanced position during wet-wringing, this being assisted, as already described, by the adjacent ribs 150 provided on the shroud inner wall. In the position shown in Figure 10, however, the teeth 134 of the wringing elements 130 protrude very much further into the interior space within the shroud, and owing to the specially shaped side faces 138, 139 of the wringing elements 130 as illustrated, substantially reduce the cross-sectional area of the void within the shroud, so that when this space is occupied by the mop elements 104, swivelling movement of the wringing elements 130 from the position shown in Figure 9 to that shown in Figure 10 causes compression of the mop elements 104 and thus squeezing of them to eject water therefrom for the purpose of dry-wringing. The swivelling movement of the wringing elements 130 from the position shown in Figure 9 into that shown in Figure 10 is caused by the mop elements 104 themselves catching on the teeth 134 as they are urged to rotate relative to the cage upon relative rotation of the shroud relative to the mop handle (with which the cage mop elements are fast) . Thus, once the mop elements have begun to catch on the teeth 134, further relative rotation of them relative to the cage urges the wringing elements 130 to swivel about their swivel axes 136 even further towards the limiting swivelling position shown in Figure 10. As the relative rotational force between the cage and the mop elements increases, so the distance through which the mop elements 130 swivel also increases, with the result that there is an increasing dry-wringing pressure exerted on the mop elements. For proper functioning of the device, it is important that even once in the limiting swivelling position shown in Figure 10, each of the wringing elements does not swivel over-centre, that is to say through an angle such that its tooth 134 crosses an imaginary line extending from the respective swivel axis 136 to the centre of the bunch of mop elements 104, which line is illustrated in the case of each wringing element by a broken line in each of Figures 9 to 12. This limited movement is achieved by appropriate positioning and configuring of the limit stops 132a on the wringing elements. This non-over centre swivelling is important for ensuring proper reverse swivelling of the wringing elements during the push-out operation when the shroud is withdrawn from the mop elements. When the bunch of mop elements 104 is in its fully dry-wrung condition, because of the twisting action which is responsible for the wringing function, the mop elements are drawn up a short distance into the shroud and their end sections are together compressed into a tight core, designated 104a in Figure 10. (In this connection it is possible, and may even be desirable, for the lower sections of the mop strip elements 104 (or whichever regions of them are gripped by the wringing elements during dry-wringing) to be calendered as part of their manufacture, in order to give them greater strength and thus to prolong their life, given the dry-wringing stresses they must withstand during multiple dry-wringing operations of the mop. ) The height of this core 104a corresponds substantially to the height of the maximum protruding portions of the teeth 134 of the wringing elements, which are the parts which actually contact and grip the mop elements to cause them to twist together. Above the core 104a the mop elements assume a less compacted configuration with a wide diameter, as designated 104b in Figure 11 (this Figure is a view from inside the shroud looking down and towards its open end, whereas Figure 10 is a view from the open end looking up inside the shroud). Thus, between the core 104a and the less compacted section 104b of the dry-wrung mop elements there is formed a generally frusto-conical shoulder 104c (Figure 10) (widening towards the top), which bears against the ramp faces 137 (see Figure 13) of the wringing elements. Having reached this condition, maximum dry-wringing has been effected and the push-out stage is ready to be carried out in order to release the wringing elements and allow the shroud to be withdrawn from the mop elements to expose them ready for use. Because the dry-wrung mop elements in the region of the shoulder 104c between the core 104a and the less compacted section 104b are relatively tightly compressed and dry, they are also somewhat stiff. As a result, when the shroud (and thus the wringing elements which are mounted fast with it) begins its upward travel relative to the mop handle (and thus relative to the mop elements which are fast with it), the relatively rigid shoulder 104c pushes against the ramp faces 137 of the wringing elements. Owing to the symmetrical shape of these ramp faces (with respect to the configuration of the teeth 134) and owing to the fact that the wringing elements have not swivelled over-centre, this pushing force causes the wringing elements to swivel in the opposite direction to before, thus causing them to swivel back towards their non-mop element-gripping position shown in Figure 9. This outward swivelling force lasts only so long as the shoulder 104c of the twisted mop elements bears against the ramp faces 137 of the wringing elements, but for practical purposes it is generally quite sufficient for effecting complete release of the wringing elements, as any residual reverse swivelling of the wringing elements which may be required to fully reach the position shown in Figure 9 will usually be completed by the mop elements themselves simply passing over the tips of the teeth 134 (and ribs 150) as the shroud completes its longitudinal withdrawal motion. This action is shown part way completed in Figure 12. In this manner, release of the wringing elements from their dry-wringing position is accomplished by simple longitudinal withdrawal of the shroud itself while the mop elements are still twisted, and it is not necessary (as one might have expected) to effect an untwisting of the mop elements before withdrawal of the shroud is possible. Indeed, such an untwisting of the mop element is undesirable, as it compromises the efficient release action of the device as described above and it can also lead to tangling up of the partly untwisted mop elements around the teeth of the wringing elements. The mop handle 102 may be made of any suitable material, such as wood or plastics, as is well known in the art. The component parts of the wringing device of the apparatus, namely the shroud, sleeve, cage and the wringing elements can all conveniently be moulded from plastics material, thereby making the mop easy and cheap to manufacture. It is to be understood that the preferred embodiments of the present invention described in detail above are purely illustrative and are not intended to limit the scope of the present invention. It will be appreciated that many variations and modifications of what has been specifically described and illustrated can be made within the scope of the invention, as will be appreciated by persons skilled in the art.

Claims: CLAIMS : 1. A mop comprising: a handle terminating at one end in a head from which extend a plurality of absorbent mop elements; a shroud rotatably mounted on the handle and slidable relative thereto between a withdrawn position in which the mop elements are exposed for mopping and an advanced position in which the mop elements are retracted within the shroud, whereby the action of sliding the shroud relative to the handle from said withdrawn position into said advanced position effects a wet-wringing of said mop elements as they are retracted within the shroud; and at least one wringing element mounted on or within the shroud and including a or a respective mop element-engagable portion, the or each wringing element being deformable and/or movable so as to be configurable in either of a first position in which retraction of the mop elements into the shroud upon sliding of the shroud from said withdrawn position to said advanced position is relatively unhindered, and a second position in which, with the shroud in its advanced position and the mop elements retracted therewithin, the or the respective mop element-engagable portion of the wringing element or elements engage and grip the mop elements within the shroud upon rotation of the shroud relative to the handle; whereby the action of rotating the shroud relative to the handle when the mop elements are retracted within the shroud and the wringing element or elements are configured in their second position, constitutes a dry-wringing of said mop elements. 2. A mop according to claim 1, wherein the wringing element or elements are provided within and fast with the shroud and are deformably configurable in either of a first configuration in which retraction of the mop elements into the shroud upon sliding of the shroud from said withdrawn position to said advanced position is relatively unhindered, and a second configuration in which, when the mop elements are retracted within the shroud, at least a portion of the or each wringing element is deformed inwardly of the shroud so as to grip the mop elements as the shroud is rotated relative to the handle; whereby the action of rotating the shroud relative to the handle when the mop elements are retracted within the shroud and the wringing element or elements are in their second, mop element-gripping configuration, constitutes the said dry-wringing of said mop elements. 3. A mop according to claim 2, wherein each wringing element is elongate and comprises a foot which is anchored to the shroud at or near its lower end, and is attached at its upper end to a common collar which surrounds and is slidable relative to the sleeve attached to the shroud, there being defined intermediate the upper and lower ends of each wringing element a respective inwardly deformable knee segment which deforms radially inwardly of the shroud when tensile compression is applied to the wringing element as force is applied which urges a reduction in the distance between its foot and upper ends. 4. A mop according to claim 3, wherein the knee segment in each wringing element is provided nearer said foot than said upper end of each wringing element. 5. A mop according to claim 3 or claim 4, wherein each wringing element comprises one or more flanges extending substantially radially outwardly from the mop element-gripping face of the wringing element. 6. A mop according to claim 1, wherein the wringing element or elements are disposed angularly around the shroud and mounted swivellably relative thereto, the or each wringing element including a respective tooth portion protruding into the interior of the shroud and having a configuration and disposition relative to the swivel axis of the wringing element such that, with the shroud in its advanced position and the mop elements retracted therewithin, rotation of the shroud relative to the mop handle in a wringing direction causes engagement of the mop elements with the tooth portion(s) of the wringing element(s) and thereby swivelling of the or each wringing element about its respective swivel axis, said swivelling motion being from a non-mop element-gripping position, in which the said retraction of the mop elements into the shroud upon sliding of the shroud relative to the handle from said withdrawn position to said advanced position is relatively unhindered, into a mop element-gripping position in which the tooth portion(s) of the wringing element(s) grip the mop elements and effect the said dry-wringing thereof upon said rotation of the shroud relative to the handle in said wringing direction. 7. A mop according to claim 6, wherein the shroud includes a cage in which are swivellably mounted the wringing elements, the cage and shroud being fast with each other, whereby rotation of the cage relative to the handle is achieved by corresponding relative rotation of the shroud. 8. A mop according to claim 6 or claim 7, wherein the cage surrounds one or more openings in the shroud through which protrude the tooth portions of the wringing elements for gripping the mop elements therewithin when the shroud is in its advanced position. 9. A mop according to claim 8, wherein the cage is defined by a pair of annular flanges extending outwardly of the shroud from the periphery of the opening or openings therein, the flanges providing anchoring points for the swivel axes of the wringing elements. 10. A mop according to claim 9, wherein the swivel axes of the wringing elements are arranged transversely to the plane of the flanges defining the cage. 11. A mop according to any one of claims 6 to 10, wherein each wringing element is mounted with its swivel axis towards the exterior of the shroud and its respective tooth portion protruding generally radially inwardly from a longitudinal edge of the wringing element opposite its swivel axis. 12. A mop according to claim 11, wherein extending from said longitudinal edge is a first side face contoured such that at least a portion of it abuts, as the wringing element swivels from its non-mop element- gripping position to its mop element-gripping position, an edge of a partitioning wall defining one side of the opening through which protrudes the tooth portion of that wringing element, and extending in a different direction also from said longitudinal edge is a second side face contoured such that at least a portion of it abuts, as the wringing element swivels froms its non-mop element-gripping position to its mop element-gripping position, an edge of a partitioning wall defining the opposite side of the opening through which protrudes the tooth portion of that wringing element. 13. A mop according to claim 12 wherein at least a portion of each side face of the wringing element(s) adjacent said longitudinal edge is shaped so as to present an upwardly and radially outwardly sloping ramp face. 14. A mop according to claim 12 or claim 13, wherein projecting from said first side face distal from said longitudinal edge is a first end stop which defines a swivel limit on the swivelling movement of the wringing element into said mop element-gripping position, and projecting from said second side face distal from said longitudinal edge is a second end stop defining a swivel limit on the swivelling movement of the wringing element into said non-mop element-gripping position. 15. A mop according to claim 14, wherein said second end stop defines a non-over centre swivel limit on the swivelling movement of the wringing element. 16. A mop according to any one of claims 12 to 15, wherein at least part of the said second side face is contoured to match the peripheral contour of the adjacent partitioning wall sections defining the opening or openings in the shroud when the wringing elements are in their non-mop element-gripping position. 17. A mop according to any one of claims 6 to 16, wherein the wringing elements are swivel biassed so that their teeth are biassed towards the interior of the shroud over a distance at the start of their swivelling travel from their non-mop element-gripping position towards their mop element-gripping position. 18. A mop according to any preceding claim, further including retention clip means for locking the shroud in its withdrawn position. 19. A mop according to any preceding claim, which includes three of said wringing elements disposed equiangularly within the shroud. 20. A mop according to any preceding claim, wherein the mop elements are calendered in the region of engagement/gripping by the wringing element(s). 21. A mop according to any preceding claim, wherein the shroud includes a plurality of smooth-faced, longitudinally extending, generally radially protruding ribs on its inner wall. 22. A method of mopping utilising a mop according to claim 1, the method including immersing the absorbent mop elements into a container of liquid, removing them therefrom and then carrying out one or both of the following wringing steps: (a) sliding the shroud relative to the handle of the mop from the withdrawn position into the advanced position to effect a wet-wringing of the mop elements as they are retracted within the shroud; (b) with the shroud in its advanced position and the mop elements retracted therewithin, and the wringing element or elements configured into their mop element- engaging position, rotating the shroud relative to the handle to effect a dry-wringing of the mop elements.

Inventors: BOYD GRAHAM PETER, DUNCAN JEFFREY, PURVIS GRANT DAVID, YOUNG DAVID IAIN, BOYD, GRAHAM, PETER, DUNCAN, JEFFREY, PURVIS, GRANT, DAVID, YOUNG, DAVID, IAIN
Applicants: UNILEVER NV, UNILEVER PLC, UNILEVER N.V.
Application year: 1994
Main classification: A47L13
IPC codes: A47L13